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sections

1 Types of Behavior

2 Behavioral InteractionsLab Observing Earthworm BehaviorLab Animal Habitats

Virtual Lab How do mealwormsbehave in response to various stimuli?

Why do animals fight?Animals often defend territories from othermembers of the same species. Fighting isusually a last resort to protect a territorythat contains food, shelter, and potentialmates.

What other behaviors might ananimal use to signal that a territory is occupied?Science Journal

Animal Behavior

D. Robert & Lorri Franz/CORBIS

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C ◆ 133

Behavior As you study behaviors, make the followingFoldable to help you find the

similarities and differences between the behav-iors of two animals.

Fold a vertical sheet of paper in half from top to bottom.

Fold in half from side to side with the fold at the top.

Unfold the paper once. Cut only the fold of the top flap to make two tabs.

Turn the paper vertically and label the front tabs as shown.

Read and Write Before you read the chapter,choose two animals to compare. As you read thechapter, list the behaviors you learn about Ani-mal 1 and Animal 2 under the appropriate tab.

STEP 4

STEP 3

STEP 2

STEP 1

How do animals communicate?One way humans communicate is by speak-ing. Other animals communicate without theuse of sound. For example, a gull chick pecksat its parent’s beak to get food. Try the labbelow to see if you can communicate withoutspeaking.

1. Form groups of students. One at a time,have each student choose an object anddescribe that object using gestures.

2. The other students observe and try toidentify the object that is being described.

3. Think Critically In your Science Journal,describe how you and the other studentswere able to communicate without speak-ing to one another.

Start-Up Activities

Preview this chapter’s contentand activities at bookc.msscience.com

Observed Behaviors

of Animal 1

Observed Behaviors

of Animal 2

D. Robert & Lorri Franz/CORBIS

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134 ◆ C CHAPTER 5 Animal Behavior

Behavior When you come home from school, does your dog run to

meet you? Your dog barks and wags its tail as you scratch behindits ears. Sitting at your feet, it watches every move you make.Why do dogs do these things? In nature, dogs are pack animalsthat generally follow a leader. They have been living with peoplefor about 12,000 years. Domesticated dogs treat people as partof their own pack, as shown in Figure 1.

Animals are different from one another in their behavior.They are born with certain behaviors, and they learn others.Behavior is the way an organism interacts with other organismsand its environment. Anything in the environment that causes a reaction is called a stimulus. A stimulus can be external, suchas a rival male entering another male’s territory; or internal,such as hunger or thirst. You are the stimulus that causes yourdog to bark and wag its tail. Your dog’s reaction to you is aresponse.

■ Identify the differences betweeninnate and learned behavior.

■ Explain how reflexes andinstincts help organisms survive.

■ Identify examples of imprintingand conditioning.

Innate behavior helps you survive on your own.

Review Vocabularysalivate: to secrete saliva inanticipation of food

New Vocabulary

• behavior • instinct

• innate • imprintingbehavior • conditioning

• reflex • insight

Types of Behavior

Figure 1 Dogs are pack animals by nature. A pack ofwild dogs must work together to survive. This domesti-cated dog (right) has accepted a human as its leader.

(l)Michel Denis-Huot/Jacana/Photo Researchers, (r)Zig Lesczynski/Animals Animals

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SECTION 1 Types of Behavior C ◆ 135

Innate Behavior A behavior that an organism is born with is called an innate

behavior. These types of behaviors are inherited. They don’thave to be learned.

Innate behavior patterns occur the first time an animalresponds to a particular internal or external stimulus. For birdslike the swallows and the hummingbird in Figure 2 building anest is innate behavior. When it’s time for the female weaverbirdto lay eggs, the male weaverbird builds an elaborate nest, alsoshown in Figure 2. Although a young male’s first attempt may bemessy, the nest is constructed correctly.

The behavior of animals that have short life spans is mostlyinnate behavior. Most insects do not learn from their parents. Inmany cases, the parents have died or moved on by the time theyoung hatch. Yet every insect reacts innately to its environment.A moth will fly toward a light, and a cockroach will run awayfrom it. They don’t learn this behavior. Innate behavior allowsanimals to respond instantly. This quick response often meansthe difference between life and death.

Reflexes The simplest innate behaviors are reflex actions. Areflex is an automatic response that does not involve a messagefrom the brain. Sneezing, shivering, yawning, jerking your handaway from a hot surface, and blinking your eyes when some-thing is thrown toward you are all reflex actions.

In humans a reflex message passes almost instantly from asense organ along the nerve to the spinal cord and back to themuscles. The message does not go to the brain. You are aware ofthe reaction only after it has happened. Your body reacts on itsown. A reflex is not the result of conscious thinking.

Figure 2 Bird nests come in different sizes and shapes. Thismale weaverbird is knotting theends of leaves together to securethe nest.

Reflex A tap on a tendonin your knee causes yourleg to straighten. This isknown as the knee-jerkreflex. Abnormalities in thisreflex tell doctors of a pos-sible problem in the centralnervous system. Researchother types of reflexes andwrite a report about themin your Science Journal.

Cliff swallows build nestsout of mud.

Hummingbirds build delicatecup-shaped nests on branchesof trees.

(l)Jack Ballard/Visuals Unlimited, (c)Anthony Mercieca/Photo Researchers, (r)Joe McDonald/Visuals Unlimited

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Instincts An instinct is a complex pattern of innatebehavior. Spinning a web like the one in Figure 3 iscomplicated, yet spiders spin webs correctly on thefirst try. Unlike reflexes, instinctive behaviors can takeweeks to complete. Instinctive behavior begins whenthe animal recognizes a stimulus and continues untilall parts of the behavior have been performed.

What is the difference between a reflex and an instinct?

Learned BehaviorAll animals have innate and learned behaviors.

Learned behavior develops during an animal’s lifetime.Animals with more complex brains exhibit morebehaviors that are the result of learning. However, the

behavior of insects, spiders, and other arthropods is mostlyinstinctive behavior. Fish, reptiles, amphibians, birds, and mam-mals all learn. Learning is the result of experience or practice.

Learning is important for animals because it allows them torespond to changing situations. In changing environments, ani-mals that have the ability to learn a new behavior are more likelyto survive. This is especially important for animals with long lifespans. The longer an animal lives, the more likely it is that theenvironment in which it lives will change.

Learning also can modify instincts. For example, grouse andquail chicks, shown in Figure 4, leave their nests the day theyhatch. They can run and find food, but they can’t fly. Whensomething moves above them, they instantly crouch and keepperfectly still until the danger has passed. They will crouch with-out moving even if the falling object is only a leaf. Older birdshave learned that leaves will not harm them, but they freezewhen a hawk moves overhead.

Figure 4 As they grow older,these quail chicks will learn whichorganisms to avoid. Describe why it is important foryoung quail to react the sametoward all organisms.

Figure 3 Spiders, like this orbweaver spider, know how to spinwebs as soon as they hatch.

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SECTION 1 Types of Behavior C ◆ 137

Imprinting Learned behavior includes imprinting, trial anderror, conditioning, and insight. Have you ever seen youngducks following their mother? This is an important behaviorbecause the adult bird has had more experience in finding food, escaping predators, and getting along in the world.Imprinting occurs when an animal forms a social attachment,like the condor in Figure 5, to another organism within a spe-cific time period after birth or hatching.

Konrad Lorenz, an Austrian naturalist, developed the con-cept of imprinting. Working with geese, he discovered that agosling follows the first moving object it sees after hatching. Themoving object, whatever it is, is imprinted as its parent. Thisbehavior works well when the first moving object a gosling seesis an adult female goose. But goslings hatched in an incubatormight see a human first and become imprinted on that human.Animals that become imprinted toward animals of anotherspecies have difficulty recognizing members of their own species.

Trial and Error Can you remember when youlearned to ride a bicycle? You probably fell manytimes before you learned how to balance on thebicycle. After a while you could ride without hav-ing to think about it. You have many skills that you learned through trial and error, such as feed-ing yourself and tying your shoes, as shown in Figure 6.

Behavior that is modified by experience iscalled trial-and-error learning. Many animalslearn by trial and error. When baby chicks first tryto feed themselves, they peck at many stonesbefore they get any food. As a result of trial anderror, they learn to peck only at food particles.

Figure 5 When feeding chicks incaptivity, puppets of adult condorsare used so the chicks don’t learn toassociate humans with food.

Figure 6 Were you able to tieyour shoes on the first attempt? List other things you do every daythat require learning.

Topic: Captive BreedingVisit for Weblinks to information about captivebreeding.

Activity Identify and describetechniques used to raise captivespecies and introduce them intothe wild.

bookc.msscience.com

(t)The Zoological Society of San Diego, (b)Margret Miller/Photo Researchers

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138 ◆ C CHAPTER 5 Animal Behavior

Conditioning Do you have an aquarium in your school orhome? If you put your hand above the tank, the fish probablywill swim to the top of the tank, expecting to be fed. They havelearned that a hand shape above them means food. What wouldhappen if you tapped on the glass right before you fed them?Soon the fish probably will swim to the top of the tank if youjust tap on the glass. Because they are used to being fed after youtap on the glass, they associate the tap with food.

Animals often learn new behaviors by conditioning. In conditioning, behavior is modified so that a response to onestimulus becomes associated with a different stimulus. There aretwo types of conditioning. One type introduces a new stimulusbefore the usual stimulus. Russian scientist Ivan P. Pavlov per-formed experiments using this type of conditioning. He knewthat the sight and smell of food made hungry dogs secrete saliva. Pavlov added another stimulus. He rang a bell before hefed the dogs. The dogs began to connect the sound of the bellwith food. Then Pavlov rang the bell without giving the dogsfood. They salivated when the bell was rung even though he didnot give them food. The dogs, like the one in Figure 7, were conditioned to respond to the bell.

In the second type of conditioning, the new stimulus is givenafter the affected behavior. Getting an allowance for doingchores is an example of this type of conditioning. You do yourchores because you want to receive your allowance. You havebeen conditioned to perform an activity that you may not havedone if you had not been offered a reward.

How does conditioning modify behavior?

Observing ConditioningProcedure1. Obtain several photos of

different foods and land-scapes from your teacher.

2. Show each picture to aclassmate for 20 s.

3. Record how each photomade your partner feel.

Analysis1. How did your partner feel

after looking at the photosof food?

2. What effect did the land-scape pictures have onyour partner?

3. Infer how advertising mightcondition consumers to buyspecific food products.

Figure 7 In Pavlov’s experi-ment, a dog was conditioned tosalivate when a bell was rung. It associated the bell with food.

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SECTION 1 Types of Behavior C ◆ 139

Self Check1. Compare and contrast a reflex and an instinct.

2. Compare and contrast imprinting and conditioning.

3. Think Critically Use what you know about conditioningto explain how the term mouthwatering food mighthave come about.

SummaryBehavior

• Animals are born with certain behaviors,while other behaviors are learned.

• A stimulus is anything in the environmentthat causes a reaction.

Innate and Learned Behaviors

• Innate behaviors are those behaviors an organ-ism inherits, such as reflexes and instincts.

• Learned behavior allows animals to respondto changing situations.

• Imprinting, trial and error, conditioning, andinsight are examples of learned behavior.

Insight How does learned behavior help an animal deal witha new situation? Suppose you have a new math problem to solve. Do you begin by acting as though you’ve never seen itbefore, or do you use what you have learned previously in mathto solve the problem? If you use what you have learned, then you have used a kind of learned behavior called insight. Insightis a form of reasoning that allows animals to use past experi-ences to solve new problems. In experiments with chimpanzees,as shown in Figure 8, bananas were placed out of the chim-panzees’ reach. Instead of giving up, they piled up boxes foundin the room, climbed them, and reached the bananas. At sometime in their lives, the chimpanzees must have solved a similarproblem. The chimpanzees demonstrated insight during theexperiment. Much of adult human learning is based on insight.When you were a baby, you learned by trial and error. As yougrow older, you will rely more on insight.

Figure 8 This illustration showshow chimpanzees may use insightto solve problems.

4. Use a Spreadsheet Make a spreadsheet of the behav-iors in this section. Sort the behaviors according towhether they are innate or learned behaviors. Then identify the type of innate or learned behavior.

bookc.msscience.com/self_check_quiz

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Instinctive Behavior Patterns Complex interactions of innate behaviors between organ-

isms result in many types of animal behavior. For example,courtship and mating within most animal groups are instinctiveritual behaviors that help animals recognize possible mates.Animals also protect themselves and their food sources bydefending their territories. Instinctive behavior, just like naturalhair color, is inherited.

Social BehaviorAnimals often live in groups. One reason, shown in Figure 9,

is that large numbers provide safety. A lion is less likely to attacka herd of zebras than a lone zebra. Sometimes animals in largegroups help keep each other warm. Also, migrating animalgroups are less likely to get lost than animals that travel alone.

Interactions among organisms of the same species are exam-ples of social behavior. Social behaviors include courtship andmating, caring for the young, claiming territories, protectingeach other, and getting food. These inherited behaviors provideadvantages that promote survival of the species.

Why is social behavior important?

■ Explain why behavioral adapta-tions are important.

■ Describe how courtship behaviorincreases reproductive success.

■ Explain the importance of socialbehavior and cyclic behavior.

Organisms must be able to commu-nicate with each other to survive.

Review Vocabularynectar: a sweet liquid producedin a plant’s flower that is themain raw material of honey

New Vocabulary

• social behavior

• society

• aggression

• courtship behavior

• pheromone

• cyclic behavior

• hibernation

• migration

Behavioral Interactions

Figure 9 When several zebrasare close together, their stripesmake it difficult for predators topick out one individual.

140 ◆ CMichael Fairchild/Peter Arnold, Inc.

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SECTION 2 Behavioral Interactions C ◆ 141

Societies Insects such as ants, bees, and the termites shownin Figure 10, live together in societies. A society is a group ofanimals of the same species living and working together in anorganized way. Each member has a certain role. Usually a spe-cific female lays eggs, and a male fertilizes them. Workers do allthe other jobs in the society.

Some societies are organized by dominance. Wolves usuallylive together in packs. A wolf pack has a dominant female. Thetop female controls the mating of the other females. If plenty offood is available, she mates and then allows the others to do so.If food is scarce, she allows less mating. During such times, sheis usually the only one to mate.

Territorial Behavior Many animals set up territories for feeding, mating, and rais-

ing young. A territory is an area that an animal defends fromother members of the same species.Ownership of a territory occurs in dif-ferent ways. Songbirds sing, sea lionsbellow, and squirrels chatter to claimterritories. Other animals leave scentmarks. Some animals, like the tiger inFigure 11, patrol an area and attackother animals of the same species whoenter their territory. Why do animalsdefend their territories? Territoriescontain food, shelter, and potentialmates. If an animal has a territory, itwill be able to mate and produce off-spring. Defending territories is aninstinctive behavior. It improves thesurvival rate of an animal’s offspring.

Figure 11 A tiger’s territory maycover several miles. It will confrontany other tiger who enters it.Explain what may be happening inthis photo.

Figure 10 Termites built thislarge mound in Australia. Themound has a network of tunnelsand chambers for the queen termite to deposit eggs into.

(t)Bill Bachman/Photo Researchers, (b)Fateh Singh Rathore/Peter Arnold, Inc.

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142 ◆ C CHAPTER 5 Animal Behavior

Aggression Have you ever watched asone dog approached another dog that waseating a bone? What happened to theappearance of the dog with the bone? Didits hair on its back stick up? Did it curl itslips and make growling noises? Thisbehavior is called aggression. Aggressionis a forceful behavior used to dominate orcontrol another animal. Fighting andthreatening are aggressive behaviors ani-mals use to defend their territories, pro-tect their young, or to get food.

Many animals demonstrate aggres-sion. Some birds let their wings droop

below their tail feathers. It may take another bird’s perch andthrust its head forward in a pecking motion as a sign of aggres-sion. Cats lay their ears flat, arch their backs, and hiss.

Submission Animals of the same species seldom fight to thedeath. Teeth, beaks, claws, and horns are used for killing prey orfor defending against members of a different species.

To avoid being attacked and injured by an individual of itsown species, an animal shows submission. Postures that makean animal appear smaller often are used to communicate sur-render. In some animal groups, one individual is usually domi-nant. Members of the group show submissive behavior towardthe dominant individual. This stops further aggressive behaviorby the dominant animal. Young animals also display submissivebehaviors toward parents or dominant animals, as shown inFigure 12.

CommunicationIn all social behavior, communication is

important. Communication is an action by asender that influences the behavior of areceiver. How do you communicate with thepeople around you? You may talk, make noises,or gesture like you did in this chapter’s LaunchLab. Honeybees perform a dance, as shown inFigure 13, to communicate to other bees in thehive the location of a food source. Animals in agroup communicate with sounds, scents, andactions. Alarm calls, chemicals, speech, court-ship behavior, and aggression are forms ofcommunication.

Figure 12 Young wolves rollover and make themselves as smallas possible to show their submis-sion to adult wolves.

Figure 13 During the waggledance, if the food source is far fromthe hive, the dance takes the formof a figure eight. The angle of thewaggle is equal to the angle fromthe hive between the Sun and nec-tar source.

Jim Brandenburg/Minden Pictures

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SECTION 2 Behavioral Interactions C ◆ 143

Courtship Behavior A male bird of paradise, shown in Figure 14, spreads its tail feathers and struts. A male sage grousefans its tail, fluffs its feathers, and blows up its two red air sacs.These are examples of behavior that animals perform beforemating. This type of behavior is called courtship behavior.Courtship behaviors allow male and female members of aspecies to recognize each other. These behaviors also stimulatemales and females so they are ready to mate at the same time.This helps ensure reproductive success.

In most species the males are more colorful and performcourtship displays to attract a mate. Some courtship behaviorsallow males and females to find each other across distances.

Chemical Communication Ants aresometimes seen moving single file toward

a piece of food. Male dogs frequently urinate on objects andplants. Both behaviors are based on chemical communication.The ants have laid down chemical trails that others of theirspecies can follow. The dog is letting other dogs know he hasbeen there. In these behaviors, the animals are using chemicalscalled pheromones (FER uh mohnz) to communicate. A chem-ical that is produced by one animal to influence the behavior ofanother animal of the same species is called a pheromone. Theyare powerful chemicals needed only in small amounts. Theyremain in the environment so that the sender and the receivercan communicate without being in the same place at the sametime. They can advertise the presence of an animal to predators,as well as to the intended receiver of the message.

Males and females use pheromones to establish territories,warn of danger, and attract mates. Certain ants, mice, and snailsrelease alarm pheromones when injured or threatened.

Figure 14 This male Emperor ofGermany bird of paradise attractsmates by posturing and fanning its tail.List other behaviors animals use toattract mates.

DemonstratingChemicalCommunicationProcedure1. Obtain a sample of per-

fume or air freshener.2. Spray it into the air to leave

a scent trail as you movearound the house or apart-ment to a hiding place.

3. Have someone try to dis-cover where you are by following the scent of the substance.

Analysis1. What was the difference

between the first and lastroom you were in?

2. Would this be an efficientway for humans to com-municate? Explain.

Michael Dick/Animals Animals

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144 ◆ C CHAPTER 5 Animal Behavior

Sound Communication Male crickets rub one forewingagainst the other forewing. This produces chirping sounds thatattract females. Each cricket species produces several calls thatare different from other cricket species. These calls are used byresearchers to identify different species. Male mosquitoes havehairs on their antennae that sense buzzing sounds produced byfemales of their same species. The tiny hairs vibrate only to thefrequency emitted by a female of the same species.

Vertebrates use a number of different forms of sound com-munication. Rabbits thump the ground, gorillas pound theirchests, beavers slap the water with their flat tails, and frogs, likethe one in Figure 15, croak. Do you think that sound communi-cation in noisy environments is useful? Seabirds that live wherewaves pound the shore rather than in some quieter place mustrely on visual signals, not sound, for communication.

Light Communication Certain kinds of flies, marine organ-isms, and beetles have a special form of communication calledbioluminescence. Bioluminescence, shown in Figure 16, is theability of certain living things to give off light. This light is pro-duced through a series of chemical reactions in the organism’sbody. Probably the most familiar bioluminescent organisms inNorth America are fireflies. These insects are not flies, but bee-tles. The flash of light that is produced on the underside of thelast abdominal segments is used to locate a prospective mate.Each species has its own characteristic flashing. Males fly closeto the ground and emit flashes of light. Females must flash ananswer at exactly the correct time to attract males.

Frogs often croak loud enough tobe heard far away.

Pileated woodpecker calls oftencan be heard above everythingelse in the forest.

Howler monkeys got their namebecause of the sounds they make.

Figure 15 Many animals usesound to communicate.

Morse Code Samuel B.Morse created a code in1838 using numbers torepresent letters. Hisearly work led to Morsecode. Naval ships todaystill use Morse code tocommunicate with eachother using huge flash-lights mounted on theships’ decks. In yourScience Journal, writewhat reasons you believethat Morse code is stillused by the Navy.

(l)Richard Thorn/Visuals Unlimited, (c)Arthur Morris/Visuals Unlimited, (r)Jacana/Photo Researchers

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NGS TITLEVISUALIZING BIOLUMINESCENCE

Many marine organisms use bioluminescence as a form ofcommunication. This visible light

is produced by a chemical reaction andoften confuses predators or attracts mates.Each organism on this page is shown in itsnormal and bioluminescent state.

Figure 16

DEEP-SEA SEA STAR The sea star uses lightto warn predators of its unpleasant taste.

▼

BLACK DRAGONFISH The black dragonfish lives in the deep oceanwhere light doesn’t penetrate. It haslight organs under its eyes that it useslike a flashlight to search for prey.

▼

JELLYFISH This jellyfishlights up like a neon signwhen it is threatened.

▼

KRILL The blue dots shown belowthis krill are all that are visible whenkrill bioluminesce. The krill may usebioluminescence to confuse predators.

▼

SECTION 2 Behavioral Interactions C ◆ 145(starfish)Peter J. Herring, (krill)T. Frank/Harbor Branch Oceanographic Institution, (others)Edith Widder/Harbor Branch Oceanographic Institution

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Uses of Bioluminescence Many bioluminescent animalsare found deep in oceans where sunlight does not reach. Theability to produce light may serve several functions. One speciesof fish dangles a special luminescent organ in front of its mouth.This lures prey close enough to be caught and eaten. Deep-seashrimp secrete clouds of a luminescent substance when dis-turbed. This helps them escape their predators. Patternsof luminescence on an animal’s body may serve as marks ofrecognition similar to the color patterns of animals that live insunlit areas.

Cyclic Behavior Why do most songbirds rest at night while some species of

owls rest during the day? Some animals like the owl in Figure 17show regularly repeated behaviors such as sleeping in the dayand feeding at night.

A cyclic behavior is innate behavior that occurs in a repeat-ing pattern. It often is repeated in response to changes in theenvironment. Behavior that is based on a 24-hour cycle is calleda circadian rhythm. Most animals come close to this 24-hourcycle of sleeping and wakefulness. Experiments show that evenif animals can’t tell whether it is night or day, they continue tobehave in a 24-hour cycle.

Animals that are active during the day are diurnal (dy UR nul).Animals that are active at night are nocturnal. Owls are nocturnal.They have round heads, big eyes, and flat faces. Their flat facesreflect sound and help them navigate at night. Owls also have softfeathers that make them almost silent while flying.

What is a diurnal behavior?

Figure 17 Barn owls usuallysleep during the day and hunt atnight. Identify the type of behavior theowl is exhibiting.

Topic: Owl BehaviorVisit for Weblinks to information about owlbehavior.

Activity List five different typesof owl behavior and describe howeach behavior helps the owl survive.

bookc.msscience.com

146 ◆ CStephen Dalton/Animals Animals

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How can you determine which animals hibernate?

SECTION 2 Behavioral Interactions C ◆ 147

Hibernation Some cyclicbehaviors also occur over longperiods of time. Hibernationis a cyclic response to coldtemperatures and limited foodsupplies. During hibernation,an animal’s body temperaturedrops to near that of its sur-roundings, and its breathingrate is greatly reduced. Ani-mals in hibernation, such asthe bats in Figure 18, surviveon stored body fat. The animalremains inactive until theweather becomes warm in the spring. Some mammals andmany amphibians and reptiles hibernate.

Animals that live in desertlike environments also go into astate of reduced activity. This period of inactivity is called esti-vation. Desert animals sometimes estivate due to extreme heat,lack of food, or periods of drought.

Figure 18 Many bats find afrost-free place like this abandonedcoal mine to hibernate for the win-ter when food supplies are low.

Average Body Temperaturesof Hibernating Animals

Animal Normal Body Hibernating Body

Temperature (°C) Temperature (°C)

Woodchuck 37 3

Squirrel 32 4

Grizzly bear 32–37 27–32

Whippoorwill 40 18

Hoary 37 10marmot

Many animals hibernate in the winter.During this period of inactivity, they

survive on stored body fat. While they arehibernating, they undergo several physicalchanges. Heart rate slows down and bodytemperature decreases. The degree towhich the body temperature decreasesvaries among animals. Scientists disagreeabout whether some animals truly hiber-nate or if they just reduce their activity andgo into a light sleep. Usually, a true hiber-nator’s body temperature will decrease sig-nificantly while it is hibernating.

Identifying the ProblemThe table on the right shows the differ-

ence between the normal body tempera-ture and the hibernating body temperatureof several animals. What similarities doyou notice?

Solving the Problem1. Which animals would you classify as true

hibernators and which would you classify aslight sleepers? Explain.

2. Some animals such as snakes and frogs alsohibernate. Why would it be difficult to recordtheir normal body temperature?

Richard Packwood/Animals Animals

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148 ◆ C CHAPTER 5 Animal Behavior

Self Check1. Describe some examples of courtship behavior and how

this behavior helps organisms survive.

2. Identify and explain two reasons that animals migrate.

3. Compare and contrast hibernation and migration.

4. Think Critically Suppose a species of frog lives close toa loud waterfall. It often waves a bright blue foot in theair. What might the frog be doing?

SummaryInstinctive Behavior Patterns

• Instinctive behavior patterns are inherited.

• Courtship and mating are instinctive for mostanimal groups.

Social and Territorial Behaviors

• Interactions among organisms of a group areexamples of social behavior.

• Many animals protect a territory for feeding,mating, and raising young.

Communication and Cyclic Behavior

• Species can communicate with each otherusing behavior, chemicals, sound, orbioluminescence.

• Cyclic behaviors occur in response toenvironmental changes.

Migration Instead of hibernating, many animals move to newlocations when the seasons change. This instinctive seasonalmovement of animals is called migration. Most animals migrateto find food or to reproduce in environments that are morefavorable for the survival of offspring. Many bird species fly forhours or days without stopping. The blackpoll warbler flies morethan 4,000 km, nearly 90 hours nonstop from North America toits winter home in South America. Monarch butterflies, shown inFigure 19, can migrate as far as 2,900 km. Gray whales swimfrom arctic waters to the waters off the coast of northern Mexico.After the young are born, they make the return trip.

Figure 19 Many monarch but-terflies travel from the UnitedStates to Mexico for the winter.

5. Solve One-Step Equations Some cicadas emerge fromthe ground every 17 years. The population of one typeof caterpillar peaks every five years. If the peak cycle ofthe caterpillars and the emergence of cicadas coincided in 1990, in what year will they coincide again?

bookc.msscience.com/self_check_quizKen Lucas/Visuals Unlimited

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Earthworms can be seen at night wrigglingacross wet sidewalks and driveways. Why don’tyou see many earthworms during the day?

Real-World QuestionHow do earthworms respond to light?

Goals■ Predict how earthworms will behave in the

presence of light.

Materialsscissors papershoe box with lid moist paper towelsflashlight earthwormstape timer

Safety Precautions

Procedure1. Cut a round hole, smaller than the end of

the flashlight, near one end of the lid.

2. Tape a sheet of paper to the lid so it hangsjust above the bottom of the box and about10 cm away from the end with the hole in it.

3. Place the moist paper towels in the bottomof the box.

4. Place the earthworms in the end of the boxthat has the hole in it.

5. Hold the flashlight over the hole and turn it on.

6. Leave the box undisturbed for 30 minutes,then open the lid and observe the worms.

7. Record the results of your experiment inyour Science Journal.

Conclude and Apply1. Identify which direction the earthworms

moved when the light was turned on.

2. Infer Based on your observations, what canyou infer about earthworms?

3. Explain what type of behavior the earth-worms exhibited.

4. Predict where you would need to go to findearthworms during the day.

ObservingEarthwDrm Behavior

Write a story that describes a day in the life of an earthworm. List activities, dangers,and problems an earthworm might face.Include a description of its habitat. For morehelp, refer to the Science Skill Handbook.

Flashlight

Earthworms

Notebook paper

Paper towel

LAB C ◆ 149

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Model and InventModel and Invent

Goals■ Research the natural

habitat and basic needsof one animal.

■ Design and model anappropriate zoo, ani-mal park, or aquariumenvironment for thisanimal. Working coop-eratively with yourclassmates, design anentire zoo or animalpark.

Possible Materialsposter boardmarkers or colored pencilsmaterials that can be used

to make a scale model

Abimal Habitats

150 ◆ C

Real-World QuestionZoos, animal parks, and aquariums are safeplaces for wild animals. Years ago, captive ani-mals were kept in small cages or behind glasswindows. Almost no attempt was made to pro-vide natural habitats for the animals. Peoplewho came to see the animals could not observethe animal’s normal behavior. Now, most cap-tive animals are kept in exhibit areas thatclosely resemble their natural habitats. Theseareas provide suitable environments for theanimals so that they can interact with mem-bers of their same species and have healthier,longer lives. What types of environments arebest suited for raising animals in captivity?How can the habitats provided at an animalpark affect the behavior of animals?

Make a Model1. Choose an animal to research. Find out where this animal is found

in nature. What does it eat? What are its natural predators? Does itexhibit unique territorial, courtship, or other types of behavior?How is this animal adapted to its natural environment?

(t)The Zoological Society of San Diego, (b)Gary Carter/Visuals Unlimited

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2. Design a model of a proposed habitat in which this animal can live successfully.Don’t forget to include all of the things, such as shelter, food, and water, that youranimal will need to survive. Will there be any other organisms in the habitat?

3. Research how zoos, animal parks, or aquariums provide habitats for animals.Information may be obtained by contacting scientists who work at zoos, animalparks, and aquariums.

4. Present your design to your class in the form of a poster, slide show, or video.Compare your proposed habitat with that of the animal’s natural environment.Make sure you include a picture of your animal in its natural environment.

Test Your Model1. Using all of the information you have gathered, create a model exhibit area for

your animal.

2. Indicate what other plants and animals may be present in the exhibit area.

Analyze Your Data1. Decide whether all of the animals studied in this lab can coexist in the same

zoo or wildlife preserve.

2. Analyze problems that might exist in your design. Suggest some ways youmight want to improve your design.

Conclude and Apply1. Interpret Data Using the information provided by the

rest of your classmates, design an entire zoo or aquariumthat could include the majority of animals studied.

2. Predict which animals could be grouped together inexhibit areas.

3. Determine how large your zoo or wildlife preserveneeds to be. Which animals require a large habitat?

LAB C ◆ 151

Give an oral presentation to another class on the importance of providing natural habitats for captive animals. For more help,refer to the Science Skill Handbook.

Dave B. Fleetham/Tom Stack & Assoc.

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A simple and surprising strollshowed that dogs really arehumans’ best friends

You’ve probably seen visually impairedpeople walking with their trusted “see-ing-eye” dogs. Over 85 years ago, a

doctor and his patient discovered this canineability entirely by accident!

Near the end of World War I in Germany, Dr. Gerhard Stalling and his dog strolled with a patient—a German soldier who hadbeen blinded—around hospital grounds.

While they were walking, the doctorwas called away. A few moments later, the doc-tor returned but the dogand the soldierwere gone!Searching the paths frantically, Dr. Stalling made an astonishing discovery. His pet had led the soldier safely around the hospital grounds.Inspired by whathis dog could do,Dr. Stalling set up the first school in theworld dedicated to training dogs as guides.

German shepherds, golden retrievers,and Labrador retrievers seem to make thebest guide dogs. They learn hand gesturesand simple commands to lead visuallyimpaired people safely across streets andaround obstacles. This is what scientists call“learned behavior.” Animals gain learnedbehavior through experience. But, a guidedog doesn’t just learn to respond to specialcommands; it also must learn when not toobey. If its human owner urges the dog tocross the street and the dog sees that a car isapproaching, the dog refuses because it haslearned to disobey the command. This trait,called “intelligent disobedience,” ensures thesafety of the owner and the dog—a sure signthat dogs are still humans’ best friends.A dog safely guides its owner across a

street.

SOMETIMES GREAT

DISCOVERIES HAPPEN BY ACCIDENT!

Write Lead a blindfolded partner around theclassroom. Help your partner avoid obstacles. Thentrade places. Write in your Science Journal about yourexperience leading and being led.

For more information, visit bookc.msscience.com/oops

German shepherds make excellent guide dogs.

(t)Walter Smith/CORBIS, (b)Bios (Klein/Hubert)/Peter Arnold, Inc.

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Types of Behavior

1. Behavior that an animal has when it’s bornis innate behavior. Other animal behaviorsare learned through experience.

2. Reflexes are simple innate behaviors. Aninstinct is a complex pattern of innatebehavior.

3. Learned behavior includes imprinting, inwhich an animal forms a social attachmentimmediately after birth.

4. Behavior modified by experience is learningby trial and error.

5. Conditioning occurs when the response to one stimulus becomes associated withanother. Insight is the ability to use pastexperiences to solve new problems.

Behavioral Interactions

1. Behavioral adaptations such as defense of territory, courtship behavior, and socialbehavior help species of animals surviveand reproduce.

2. Courtship behaviors allow males and femalesto recognize each other and prepare to mate.

3. Interactions among members of the samespecies are social behaviors.

4. Communication among organisms occursin several forms, including chemical, sound,and light.

5. Cyclic behaviors are behaviors that occur inrepeating patterns. Animals that are activeduring the day are diurnal. Animals that areactive at night are nocturnal.

CHAPTER STUDY GUIDE C ◆ 153

Copy and complete the following concept map on types of behavior.

Behavior

such as such as Insight

Trial and error

such as such as

such as such as

can be can be

bookc.msscience.com/interactive_tutor

Innate

(l)Valerie Giles/Photo Researchers, (r)J & B Photographers/Animals Animals

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Explain the differences between the pairs ofvocabulary words given below. Then explainhow the words are related.

1. conditioning—imprinting

2. innate behavior—social behavior

3. insight—instinct

4. social behavior—society

5. instinct—reflex

6. hibernation—migration

7. courtship behavior—pheromone

8. cyclic behavior—migration

9. aggression—social behavior

10. behavior—reflex

Choose the word or phrase that best answers thequestion.

11. What is an instinct an example of?A) innate behaviorB) learned behaviorC) imprintingD) conditioning

12. What is an area that an animal defendsfrom other members of the same species called?A) society C) migrationB) territory D) aggression

13. Which animals depend least on instinctand most on learning?A) birds C) mammalsB) fish D) amphibians

14. What is a spider spinning a web an example of?A) conditioning C) learned behaviorB) imprinting D) an instinct

15. What is a forceful act used to dominate or control another called?A) courtship C) aggressionB) reflex D) hibernation

16. What is an organized group of animalsdoing specific jobs called?A) community C) societyB) territory D) circadian rhythm

17. What is the response of inactivity andslowed metabolism that occurs during cold conditions?A) hibernation C) migrationB) imprinting D) circadian rhythm

18. Which of the following is a reflex?A) writing C) sneezingB) talking D) riding a bicycle

Use the photo below to answer question 19.

19. The photo above is an example of whattype of communication?A) light communicationB) sound communicationC) chemical communicationD) cyclic behavior

154 ◆ C CHAPTER REVIEW

aggression p. 142behavior p. 134conditioning p. 138courtship behavior p. 143cyclic behavior p. 146hibernation p. 147imprinting p. 137innate behavior p. 135

insight p. 139instinct p. 136migration p. 148pheromone p. 143reflex p. 135social behavior p. 140society p. 141

bookc.msscience.com/vocabulary_puzzlemaker

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20. Explain the type of behavior involved whenthe bell rings at the end of class.

21. Describe the advantages and disadvantagesof migration as a means of survival.

22. Explain how a habit, such as tying yourshoes, is different from a reflex.

23. Explain how behavior increases an animal’schance for survival using one example.

24. Infer Hens lay more eggs in the springwhen the number of daylight hoursincreases. How can farmers use thisknowledge of behavior to their advantage?

25. Record Observations Make observations of adog, cat, or bird for a week. Record whatyou see. How did the animal communicatewith other animals and with you?

26. Classify Make a list of 25 things that you doregularly. Classify each as an innate orlearned behavior. Which behaviors do youhave more of?

27. Concept Map Copy and complete the follow-ing concept map about communication.Use these words: sound, chirping, biolumi-nescence, and buzzing.

28. Poster Draw a map showing the migrationroute of monarch butterflies, gray whales,or blackpoll warblers.

CHAPTER REVIEW C ◆ 155

Use the graphs below to answer question 29.

29. Bee Foraging Bees were trained to forage from1:00 P.M. to 2:30 P.M. in New York and then wereflown to California. The graphs above show thenumber of bees looking for food during the firsttwo days in California. What was the differencein peak activity from day 1 to day 2? Was therea difference in the proportion of bees activeduring peak hours ?

30. Bird Flight A blackpoll warbler flies 4,000 kmnonstop from North America to South Americain about 90 hours. What is its rate of speed?

Day 2

Day 1

0

60

40

20

Time

Nu

mb

er o

f bee

s

8:00 A.M.

9:00 A.M.

10:00 A.M.

11:00 A.M.

12:00 P.M.

1:00 P.M.

2:00 P.M.

0

120

80100

604020

Time

Nu

mb

er o

f bee

s8:00 A.M.

9:00 A.M.

10:00 A.M.

11:00 A.M.

12:00 P.M.

1:00 P.M.

2:00 P.M.

Communication

Light

can be

such as such assuch as

can be

bookc.msscience.com/chapter_review

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Record your answers on the answer sheetprovided by your teacher or on a sheet of paper.

1. Which of the following is true about innatebehaviors?A. They are learned behaviors.B. They are observed in only some animals.C. They are the result of conscious thought.D. They include reflexes.

2. A spider spinning its web is an example ofa(n) A. reflex. C. imprinting.B. instinct. D. conditioning.

Use the illustration below to answer questions 3 and 4.

3. The illustration above describes what kindof learned behavior?A. conditioningB. trial and errorC. imprintingD. insight

4. Which of the following best describes thislearned behavior?A. The dog learns to salivate when pre-

sented with food.B. The dog learns to eat only if the bell is

rung.C. The dog is conditioned to stop salivating

when a bell is rung.D. The dog is conditioned to salivate when

a bell is rung.

5. Which of the following is an example ofterritorial behavior?A. A honeybee performs a waggle dance

when it returns to the hive.B. A peacock fans his tail while approach-

ing a peahen.C. A mountain goat charges and attacks an

unfamiliar mountain goat.D. A group of bats remain in hibernation

for the winter.

Use the photo below to answer questions 6 and 7.

6. The male wolf lying on its back is displayingwhat kind of behavior to the other male wolf?A. aggressive behaviorB. submissive behaviorC. cyclic behaviorD. courtship behavior

7. Which of the following statements bestdescribes the behavior of the wolf that isstanding?A. The wolf is displaying its dominance

over the wolf on the ground.B. The wolf is displaying courtship behav-

ior to the other wolf.C. The wolf is using bioluminescence to

communicate with the other wolf.D. The wolf is watching the other wolf per-

form the waggle dance.

156 ◆ C STANDARDIZED TEST PRACTICEJim Brandenburg/Minden Pictures

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STANDARDIZED TEST PRACTICE C ◆ 157

Record your answers on the answer sheetprovided by your teacher or on a sheet of paper.

8. Give an example of an innate behavior ina hummingbird.

9. Which is simpler and more automatic,instincts or reflexes?

Use the illustration below to answer questions 10 and 11.

10. What type of learning is shown above?

11. What is required in order for an animal to use this type of learning to solve aproblem?

12. Could a young child solve a problem usinginsight? Why or why not?

13. Give three examples of social behaviors.

14. Why might an animal be submissive toanother animal?

Record your answers on a sheet of paper.

15. Compare and contrast the innate behav-iors of animals with short life spans andanimals with long life spans.

16. Give three examples of ways biolumines-cence is used for communication.

17. Explain the difference between a diurnalanimal and a nocturnal animal. Give anexample of each.

18. Compare and contrast hibernation andestivation.

Use the photo below to answer questions 19 and 20.

19. Explain the type of behavior that is shownabove.

20. How is this behavior related to why zoosfeed newborn condors with hand puppetsthat look like adult condors?

21. A male antelope approaches a female ante-lope during the breeding season. Is themale antelope responding to an externalstimulus, an internal stimulus, or both?Explain.

bookc.msscience.com/standardized_test

Compare and Contrast Make sure each part of the question isanswered when listing discussion points. For example, if thequestion asks you to compare and contrast, make sure you listboth similarities and differences.

PhotoDisc

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